Containers are commonly used in the storage and transportation of fluids, typically viscous liquids, such as tomato paste or other food products. The containers are palletized and have rigid walls and a lid. The containers define an interior which supports a bag filled with the fluid. Commonly these containers are collapsible for reuse so that they require less space for storage and transport when empty. The container must be strong enough when assembled to survive the rigors of transportation and still be easily stackable when collapsed to maximize warehouse space.
Standardized sizes of forklifts, tractor trailer rigs, railroad cars, and other shipping vehicles have resulted in the proliferation of containers which have a footprint similar to that of a standard 44-inch by 48-inch pallet and which have a height of approximately 30 to 50 inches. Containers which deviate significantly from these dimensions are less economical in that they do not fit as easily onto various transportation systems and are not as easily manipulated by commonly available handling means such as forklifts.
Containers of this type have commonly been made from plywood or other heavy and strong, yet increasingly expensive materials. The four walls of these cubic containers are held together by, inter alia, a combination of horizontal straps girding the walls and L-shaped brackets at corners between the walls which are attached to two of the four walls. The walls are held adjacent the base by straps which gird the walls, lid and pallet in vertical planes.
While these prior art containers can perform the requisite task of containing and supporting liquids during transport, they exhibit a number of drawbacks. Wood has a tendency to splinter and crack. Thus, joints cannot be formed within the wooden walls themselves as they are typically not sufficiently strong to withstand the hydrostatic forces exerted from within by the contained liquids. Thus, corner supports are added to the wooden walls and straps are utilized to gird and support the walls. These added accessories not only increase material cost to form the container but also require additional labor to assemble the container, thus increasing the total unit cost for the container. These accessories also add weight to the container, complexity and expense in handling the container. Additionally, cost and weight comparisons of container walls formed from wood versus alternative materials suggest that alternative materials may compete with wood in forming the container. Such materials could be formed from synthetic materials into strength optimizing geometries which are difficult to form in wood materials. As environmental concerns over the management of forests and forest products has increased, the use of wood products has become less desirable environmentally and economically.
Accordingly, a need exists for a container utilizeable in supporting fluids and other substances which exert hydrostatic force. Such a container is needed which can resist the hydrostatic forces exerted by substances within the container without the need for straps or accessories. Additionally, a container is needed which exhibits a geometry which can be readily formed from alternative materials, such as high strength recyclable plastics, so that a dependence on forest products is reduced or eliminated.
The following prior art reflects the state of the art of which applicant is aware and is included herewith to discharge applicant's acknowledged duty to disclose relevant prior art. It is stipulated, however, that none of these references teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as disclosed in greater detail hereinafter and as particularly claimed.
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